investigation with so much attention focused on gm. The CEO testifying. On capital heil about those recalls. We were asked about those recalled makes and models. Buyers would never know. ABC's gio Benitez and our producers going undercover. Reporter: After gmc Mary Bara faced intense grilling on capital hill, new questions over recalled cars from oer manufacturers as well. Still on the road and up for sale without repairs. More than 3 million of them, many at used car lots. If you don't check, you might never know. For ABC news investigation, we had our producer go under cover to five used car lots. To see if salesmen would be up front or knowledgeable about recalled cars. Two of them did mention recall. The cobalt has a recall on it right now. About the ignition switch. Reporter: At another dealer. Is it safe? Listen, I just woke up. For being what it is, it's safe. There's nothing I need to know about that car? Nothing. All you got to do is throw a battery in there. You saw my write-up, right? Yeah. I'm as honest as it's going to be. Reporter: We went back. You said this car was safe but it actually has a recall. Well recalls get recalled once you register the car. We don't know there's a recall or not. We pulled it up. On gm.com. There is the recall. We don't get these. Reporter: But it's easy. Take that cobalt, we're on gm.com. We plugged in the vin and id number and we see it has a recall. There's no law that requires used car dealers to tell customers about open recalls but legislators in California and New York are trying to change that. Moving forward, what do you think you're going to do. I'm going to start to look and see if there's a recall or not. And the national independent auto association says dealer should take extra steps and to repair sift related recalls they know about and Angelo called us and said he has taken the car off the lot. He's checking the vin Numbers now.

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